diff --git a/acme/acme/challenges.py b/acme/acme/challenges.py
index 250a42845..3eadfd17d 100644
--- a/acme/acme/challenges.py
+++ b/acme/acme/challenges.py
@@ -33,7 +33,7 @@ T = TypeVar('T', bound='_JSONObjectWithFields')
 R = TypeVar('R', bound='Challenge')
 
 
-# TODO: Remove this class once JSONObjectWithFields in josepy becomes generic.
+# TODO: Remove this class once JSONObjectWithFields.from_json in josepy becomes generic.
 class _JSONObjectWithFields(jose.JSONObjectWithFields):
     """Generic version of jose.JSONObjectWithFields"""
 
diff --git a/acme/acme/messages.py b/acme/acme/messages.py
index d1482be34..3375528fb 100644
--- a/acme/acme/messages.py
+++ b/acme/acme/messages.py
@@ -68,7 +68,8 @@ ERROR_TYPE_DESCRIPTIONS.update(dict(  # add errors with old prefix, deprecate me
 T = TypeVar('T', bound='_JSONObjectWithFields')
 
 
-# TODO: Remove this class once JSONObjectWithFields and ImmutableMap in josepy becomes generic.
+# TODO: Remove this class once JSONObjectWithFields.from_json and ImmutableMap.update
+#  in josepy become generic.
 class _JSONObjectWithFields(jose.JSONObjectWithFields):
     """Generic version of jose.JSONObjectWithFields"""